Polycyclic Aromatic Hydrocarbons Concentrations in Soils from Power Plant Stations in Universities in Port Harcourt, Rivers State, Niger Delta, Nigeria

Abstract

Soil contamination as a result of human interferences with nature is a common occurrence all over the world. Soil samples were collected from three universities (Ignatius Ajuru University of Education (IAUE), University of Port Harcourt (UNIPORT) and the Rivers State University (RSU) in Port Harcourt, Rivers State. The soils were taken at the points where the different institutions generate electricity with diesel powered generators. The soil samples were collected from the surface to a dept of 30 cm and were put into tightly closed glass containers. They were transported to the laboratory and prepared by standard methods of extraction and purification. The extracts were analyzed with a gas chromatography – mass spectrophotometry instrument to obtain the various fractions of PAHs present in the samples. It was observed that all the 16 priorities PAHs were present in all the samples from the station. The total concentrations of PAHs showed that IAUE>UNIPORT>RSU with respective values of 18.18, 16.64 and 16.53 mg/Kg. Benz(a)anthracene was observed to be the most abundant PAH in all the stations with a value of 2.11±0.14, 2.01±0.51 and 2.10±0.57 mg/Kg for IAUE<UNIPORT and RSU respectively. Fingerprinting and source diagnosis identified only one source of PAHs being pyrogenic sources of PAHs in the three stations. Ring size analysis showed the order 2-3>4>5>6 rings. The concentrations of carcinogenic and non-carcinogenic PAHs were almost in equal proportions in the soils examined. Therefore, the workers involved directly with the electrical generation on these campuses should adequately protected and informed on the consequences of contact with the soil and the gases that come out of the exhaust. Keywords: polycyclic aromatic hydrocarbons, soil, fingerprinting, power generating stations, pollution, human influence